1. Technical Field
The present invention relates to image reproducing apparatuses provided with auto-restoration capabilities, and in particular relates to monitoring and display of auto-restoring functions in such image reproducing apparatuses.
2. Description of Related Art
Auto-restoration capabilities in image reproducing apparatuses such as photocopying machines, facsimile devices and page printers are known. Auto-restoration capabilities enable the image reproducing apparatuses to resume operations despite minor machine malfunctions. Auto-restoring image reproducing apparatuses, wherein normal machine performance has been impeded due to mechanical or like trouble, can automatically regain minimum requisite functions by executing various restorative operations.
Machine operating conditions are constantly monitored in auto-restoring image reproducing apparatuses. When it is thus determined that there has been machine a malfunction, the type of fault is diagnosed. According to the fault diagnosis, the controller formulates a restoration plan which will fulfill functional operability of the device. The controller then directs the machine to execute restorative, usually compensatory, operations according to the restoration plan. After restorative operations have been finished, a machine operating panel displays the fact that recovery from a malfunction has been accomplished by auto-restoration.
Functional operability does not mean complete restoration of the image reproducing apparatus to its normal operating condition prior to malfunction. Rather, functional operability is recovery, properly only temporary, of requisite machine functions following malfunction. Machine functions are recovered by restorative operations which, for example, compensate for a malfunctioning component.
More specifically, in image reproducing apparatuses having this sort of auto-restoration capability, depending on the nature of the fault, there are instances in which machine operations are restored from a malfunction condition by controlling select components associated with the malfunctioning part to operate abnormally.
If the developing roller in a photocopying machine, for example, does not conduct development bias satisfactorily, the result may be overly dark, faulty copy images. In this case, increasing above normal control threshold the amount by which the exposure unit exposes the photoconductor drum, and reducing below normal control threshold the voltage at which the main charger charges the photoconductor drum can serve to maintain machine functionality. Since operability is only restored temporarily in such cases, maintenance work, (replacing the developer unit, for example), must be carried out by a service engineer in order to enable the machine control functions to return to normal.
Accordingly, with image reproducing apparatuses having an auto-restoring function as described above, the operating panel displays the fact that auto-restoration has enabled the machine to recover from a malfunction. Nevertheless, since functionality has been restored and the image reproducing apparatus appears on the surface to be operating normally, a photocopying machine user may neglect to contact a service engineer. Subsequently, in the event the same malfunction occurs again, the machine may not be able likewise to regain operability through its auto-restoration capability.
A service engineer, when summoned, will carry out maintenance work on the machine making reference to a service manual. In the foregoing example, for instance, the service approach would be based on the observation that the copy images are too dark. However, the cause (i.e., the fact that there is a fault in the developer unit, rather than in the main charger or the exposure unit) would be neither clearly nor immediately understandable, encumbering the maintenance work and making restoration of the machine from its faulty condition more time-consuming than it might be otherwise.